Carbon-consuming galvanic cell.



E. W. JUNGNER.

' oABBoN GONSUMING GALVANIG CELL.

I APPLICATION FILED JUNE 27, 1906.

919,022. Patented Apnzo, 1909.

2 SHEETS-'SHEET 1.

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E. W. JUNGNER. CARBON GONSUMING GALYANIG GELL.. l

AII'PLIGATION EILBD JUNE 27, 1906. I

Paiaented Apr. 2.0, 1909.

2 SHEETS-SHEET 2.

ERNST WALDEMAR .TUNGNER, OF KNEIPPBADEN, NORRKING, SWEDEN.

CARBON-CONSUMING GALVANIC CELL.

Specification of Letters Patent.

Patented April 2o, k1909.

Application filed June 27, 1906. Serial No. 323,678.

To all whom it may concern:

Be it known that I, ERNST VALDEMAR JUNGNER, a subject of the King ofSweden, residing at Kneippbaden, Norrkping, Sweden, have inventedcertain new and useful Improvements in Carbon Consumingr Galvanic Cells;and l do hereby declare theV following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawings, and 4to letters or figures of referencemarked thereon, which form a part of this specification.

It has heretofore been proposed to burn 7 carbon in the cold in galvanicbatteries by connecting the same in a suitable electrolyte withsubstances having the property of giving up oxygen with great facility,such as 4peroxid of lead, exothermic combinations of chlorin and oxygen,or the like. As a suitable electrolyte dilute sulfuric acid has beenused. As is well known, as the carbon becomes oxidized by these highlydepolarizing substances, it is possible to obtain with such a cell acertain slight combustion or oxidation of the carbon anodes. Bysubstituting for said highly depolarizing substances the oxygen of theair, the depolarizing power of which is quite low, no oxidation orcombustion worth mentioning is obtained, owing to the fact that theelectro-activity of the carbon in dilute sulfuric acid, at ordinarytemperature, is very inconsiderable.

I have discovered that the electro-activity of amorphous carbon insulfuric acid will be considerably increased the more the acid isconcentrated. By using an acid containing 50% I-I,SO pronounced electroactivity occurs, and by using an acid containing 90% sulfuricmono-hydrate, it is possible to obtain from a determined quantity ofcarbon connected with a constant depolarizer, a quantity of energy perunit of time about ten times greater than the energy obtained from thesame quantity of carbon in an acid of the concentration ordinarily usedfor electro-chemical purposes. Consequently a considerable galvan'icoxidation of the carbon by means of the oxygen of the air is obtained.

Concentrated sulfuric acid, however, as is well known, is a very badconductor of electricity, the temperature of the acid may be raisedsomewhat over the ordinary temperature in order to increase itsconductivity, consequently the electro-activity of the carbon alsobecomes further increased, principally for the reason that by theincreased temperature certain reactions between the amorphous carbon andthe sulfuric acid occur by which highly reducing gases are formed.

rfhe following general reaction is supposed to take place:

If the element is inactive and the heating moderate, the gases arecondensed on the surface of the carbon, whereby further reactions areprevented or delayed.

lf the carbon is put in conductive connection with an electrode havingthe property of absorbing the oxygen of the air, the following reactionsare supposed to take place:

lVhile the gases condensed on the surface of the carbon become oxidizedin this way, the final result being carbonic acid escaping from thebattery, new gases are continually produced and a continuous working gaselement is thus created in which the electrolyte remains unchanged.

The present invention relates to a galvanic cell, consisting of an anodeof amorphous carbon, in combination with a suitable air depolarizer, inan electrolyte consisting of concentrated sulfuric acid, preferablyheated, with or without addition of other electrolytes.

rl.`he oxygen of the atmospheric air may be introduced into the cathodein such a way that the latter is surrounded by a depolarizingelectrolyte, (which after giving up oxygen has the property of againtaking up the same from the atmospheric air,) or by making the cathodeitself porous and oxygen absorbing. In both cases it is convenient tofacilitate the supply of the oxygen of the air to the electrolyte or tothe cathode by mechanical means. rl"he above mentioned arrangements maysuitably be used in combination with each other.

As heated, concentrated sulfuric acid in the presence of oxygen exerts ahighly oxidizing effect, it is in this element a matter of utmostimportance that the cathode be made of a substance completelyindifferent in the said electrolyte. I have found that, besides theprecious metals, only certain species of graphite z'. c. those which aremost stable against oxidation, are suitable for this purpose.

The preparation of cathodes of a suitable form from pulverized graphitemay be done in the following manner The graphite is moistened with adilute solution of waterglass, after which the mass is pressed under aconsiderable pressure, into molds of desired form. The brick thus formedis then removed from the mold and immersed in a solution of a salt ofmagnesium or other suitable metal, whereby magnesium or other silicates,insoluble in the sulfuric acid, are formed, said silicates having theproperty of binding together the particles of graphite. The alkalinesalt is removed by immersing the electrode in water. Bricks of graphitecan also be manufactured by mixing thelatter with glass powder andheating the mixture to the melting temperature of the glass.

Electrodes produced in the manner described oifer in the present casethe same advantages as those of precious metals and can also be madeporous, and are, consequently, to a certain degree oxygen-absorbing.

The electrodes are preferably made in the forni of closely perforatedtubes a, as illustrated in the annexed drawing, forming part of thisspecication, and in which- Figure l represents an electrode in verticalcross-section. Fig. 2 represents a cell in vertical section, and Fig. 3shows in section two complete cells coupled together.

The tubes a are closed atthe lower end and provided with plugs y2 at theupper end. Air is forced in at the end at Z through pipe g that passesthrough the plug 29 and escapes through the openings 7i in the sides ofthe electrode into electrolyte, traversing same, and then escapesthrough a suitable outlet, opportunity being thereby givento theelectrolyte as well as to the porous electrode to absorb oxygen, andmoreover, the active surface of the depolarizer is always in contactwith the oxygen.

he carbon used at the anode consists of conducting carbon, such as cokeor gas-coal. Non-conducting carbon, such as hard coal, can be madeelectrolytically active by pulverizing and mixing the same with finelydivided graphite that is oxidizable with difficulty, and then formingbricks of the mixture in the manner described above, or in any othermanner. rI`he amorphous carbon then reacts with the sulfuric acid andbecomes oxidized thereby, while the graphite remains unchanged and maybe used repeatedly,

As admixtures to the electrolyte, at the same time facilitating thedepolarization and absorbing and delivering oxygen, I use eithermtrogenous gases, such as or chlorin combinations of such gases, saidsubstances, as is known, combining chemically with concentrated sulfuricacid. Also sulfates of such metal radicals as are capable of formingmore than one sulid, such as sulfate of manganese, chromium, iron,copper, mercury and the like may be used. The nitrogenous gases may bedirectly supplied by introducing the same in the acid. The salts aresuitably obtained by dissolving the corresponding metal or metal oxid inthe acid. Amixture of nitrogenous gases with such salts is especiallysuitable. If such intermediary substances are used the followingreactions, by way of example, take place in connection with formula l:

H2-l-H,SOd-NOgzIIgO-l-I'lzSO-l-NO and further by air oxidation:l'\T()+O:N()2

and as an example: CO-tQMSO-l-HZOIGOH-MQSQL-l-HZS, and furthermore byair oxidation:

M2SO4-l-H2SCi-l-OzQMSO-i-Hg() in which latter formulae M designates ainetallic radical, the valence of which varies between l and 2. Suchreactions also take place simultaneously and in combination with eachother.

In the most simple form a cell of the type indicated may be constructedas follows: On the bottom of a vessel of lead, or of wood lined withlead, or of earthenware, or of any other suitable material, pieces ofcoke 7c are placed, and over them a pei'- forated disk of lead or anyother suitable material coated with graphite is fitted in. The purposeof this disk is by means of its weight to keep the pieces of coke inconducting contact with each other, but the disk also forms t-heinactive conductor for the anode thus formed. The cathode consists of aporous brick c of scale or flake graphite that is oxidizable withdifliculty. The vessel is filled up with concentrated sulfuric acid to aheight slightly exceeding the lower surface of the brick e, the levelbeing marked on the drawing by the lines y-iz Then the vessel is placedin another, larger vessel 'v of suitable material, resting upon thesupports p. The space between the two vessels is closed by a cover fm,through which pipes fr are run, for the admission and discharge of thesteam, so that the electrolyte may-be heated above 30 C. 7" is adischarge pipe for the water of condensation. The whole complex is thenput into a still larger' vessel lw and the space between the Walls isfilled With a heat insulating material c, such as saw-dust or the like.

ig. 3 shows an improvement, for aequiring a more eiicacious and rapiddepolarization of the cathode. The electrodes are here separated by aporous partition In, of a material which is not'affected by theelectrolyte, such as asbestos. lith this arrangement, however, the sameinconvenience arises as in other galvanic elements and electrolyticapparatus that are provided with porous partition Walls, namely that adil'lusion occurs between the different iiuid compartments separated bythe porous partition. Owing to this diffusion a depolarizing electrolytewould in the present case penetrate the porous partition and give riseto local reactions at the anode, the consequence being that the Workingtension would be essentially decreased. In order to obviate thedetrimental effect of said diffusion, the porous partition is made ofconducting material indifferent in heated concentrated sulfuric acid,such as graphite, said partition being moreover put in conductingconnection With the cathode. The liquid, diffusing through the pores ofsaid partition, by this arrangement acts as a depolarizer, therebydelivering oxygen, and consequently thereafter being incapable ofgir-'ing rise to local reactions at the anode. This arrangement hasproven especially practical when using nitrogenous gases or nitric acidin the electrolyte, as said gases or said acid are all reduced bypassing through the pores of the carbon partition to gaseous NO, saidgaseous product rising to the surface of the electrode, Where it isagain oxidized by the air and combined With the concentrated sulfuricacid.

The cathode consists of closely perforated tubes a of bricked graphite,see Fig. l. A rod la, also of graphite and provided With projections uof the same material, (said rods being, las shown on the drawing,exactly fitted in the tubes a) serves as a conductor common to all ofsaid tubes a. Small pipes .s of glass or other material, are

vfitted in through the stoppers u and the rod terials having the sameproperty. 1n Fig. 8

two elements of this kind are shown coupled together. The couplingdevices, especially the ones adapted for the admission of air, Water andsteam, may be arranged in parallel if so cesired.

ln order to introduce the air in a dry state, the same is previouslyconducted through a vessel filled up with sulfuric acid or otherWater-absorbing material. The escaping air, after leaving the cells andcommingled with vapors of sulfuric acid or nitrogenous gases, isconducted through the `vessel .e filled with refrigerated concentratedsulfuric acid.

rllhe uf'orlring tension at each element at normal charge will, in roundnumbers, be half a volt. The theoretical tension of the combinationcarbon-oxygen being about one volt, about 50% of the energy of thecombustion of carbon is thus utilized, z'. e., about ten times as muchas in a modern steam engine.

1t may be observed, that the consumption ofthe carbon, contrary to whatis the case in steam engines, automatically conforms to the quantity ofthe electric current taken from the battery, and the Wasting or uselessconsumption of combustible material is completely obviated.

l claimi. ln a primary galvanic element, an anode of amorphous carbon,an electrolyte of concentrated sulfuric acid and a cathode insoluble inthe electrolyte and a depolarizer of atmospheric air.

2. 1n a primary galvanic element, an anode of amorphous carbon, anelectrolyte containing sulfuric acid in concentrated form, a cathode andmeans to supply air to the cathode.

S. 1n a primary galvanic element, a suitable electrolyte, a carbon anodecapableV of being oxidized by the electrolyte, and a graphite cathodeinsoluble in the electrolyte.

at. 1n a primary galvanic element, a suitable electrolyte, a carbonanode capable of being oxidized by the electrolyte, a graphite cathodesubstantially insoluble in the electrolyte, and means to supply air tothe cathode to depolarize the same.

5. 1n a primary galvanic element, an electrolyte of concentratedsulfuric acid, an anode of amorphous carbon, a cathode of graphite thatis oxidizable With diificulty and means to supply air to the cathode.

G. ln a primary galvanic element, an electrolyte of concentratedsulfuric acid containing a compound capable of giving off oxygen andre-combining with oxygen again, a cathode insoluble in the electrolyte,means to maintain the electrolyte at a temperature above normal and acarbon anode.

7. In a primary galvanic element, an electrolyte of sulfuric acidcontaining a compound capable of giving up andrecombining With oxygenagain, an anode of carbon, a cathode of carbon, means to supply air tothe cathode, and means to maintain the electrolyte heated above normaltemperature.

8. 1n a primary galvanic element, an electrolyte of sulfuric acid, ananode of electrolyte to maintain the carbon particles in contact, acathode of graphite that is oxidizable with diilicnlty, a porouspartition separating` the anode and cathode, means to heat theelectrolyte above normal7 and means to supply air to the cathode.

In testimony, that I claim the foregoing as my invention, l have signedmy name 2o in presence of two subscribing Witnesses.

ERNST WALDEMAR JUNGNER.

fitnesses T. BORJE, Asn XV. NORDSTROM.

